In recent years, the capacity of a NAND flash memory, which is a non-volatile semiconductor storage device, has increased and attention has been paid to an SSD (Solid State Drive) provided with the NAND flash memory.
In the SSD, the number of NAND flash memories which are operated at the same time tends to increase in order to improve the data access performance. However, when the number of NAND flash memories which are operated at the same time increases, power consumption (current consumption) increases during data access. Therefore, it is preferable to reduce the maximum power consumption (peak power) of the storage device during data access.